1. Field of the Invention
The subject invention relates to telephone accessories and, more particularly, to a novel telephone accessory incorporating a keyboard lock mechanism adapted to prevent operation of keys on a pushbutton keyboard.
2. Brief Description of the Prior Art
In the past, a variety of lock mechanisms have been provided for use in connection with rotary telephone dials for prohibiting unauthorized use of the telephone. One such device fully occupies one or more of the finger holes in the rotary dial and strikes against the finger stop as the dial is rotated to prevent further rotation of the dial. Also, other devices have been provided which operate solely on the dial while permitting the handset to be raised from the telephone cradle in the event an incoming call is received. Therefore, normal operation of the telephone is not inhibited except for the procedure of dialing out.
However, with the advent of pushbutton keyboards, no moving parts are involved such as the rotary dial employed so that lock mechanisms attended thereto cannot be used with the pushbutton keyboard. It is still desirable to permit the handset to be raised from the cradle to receive incoming calls while at the same time preventing outgoing calls.
Therefore, a longstanding need has existed to provide a lock mechanism for a pushbutton keyboard which will prevent depression of the keys or buttons but which will permit full operation of the handset such as for answering incoming calls.